Template · Service and panels

Feeder to detached garage or ADU single line diagram

Underground feeder, building disconnect and local grounding electrode. Use this for a feeder to a separate building such as a garage, a workshop or an ADU: an underground four-wire feeder, a disconnect at the building and a grounding electrode there.

A free template with typical ratings, conductor callouts and general notes. Open it, change what differs on your job, fill in the title block and export a PDF.

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Feeder to detached garage or ADU single line diagram: underground feeder, building disconnect and local grounding electrode. — Feeder to detached garage or ADU. 16 devices on an 11 × 17 in sheet with a title block and notes column.

What the reviewer checks on this drawing

The reviewer checks the four-wire feeder with the neutral isolated at the detached building, the local grounding electrode, the building disconnect, and the burial depth for the wiring method.

What the drawing shows

Every device on the sheet, in the order power reaches it.

Symbol	Label	Rating or detail	Conductors feeding it
Utility source	Utility service	120/240V 1φ 3W
Meter	Utility meter	200A socket	Service conductors, per utility
Circuit breaker	200A 2P	Main breaker
Panel	Main panel	200A bus · 120/240V
Circuit breaker	Existing	Branch breakers
Load	Existing loads
Circuit breaker	60A 2P	Feeder
Disconnect switch	Building disconnect	60A · at detached structure	3 #6 Cu + #10 G, Sch 40 PVC underground
Panel	Garage / ADU panel	100A MLO · neutrals isolated
Ground	Grounding electrode	At detached structure
Circuit breaker	20A 1P
Load	Receptacles
Circuit breaker	15A 1P
Load	Lighting
Circuit breaker	30A 2P
Load	Mini-split

Notes on the sheet

Four-wire feeder: neutral isolated and equipment ground bonded at the detached structure.
Grounding electrode installed at the detached structure and connected to the equipment grounding bar.
Burial depth per the adopted code for the wiring method used.

Diagram is schematic and not to scale. Field-verify existing equipment ratings. Ratings and conductor sizes shown are typical. Confirm against the adopted code, the equipment listing and a load calculation before installation. Code references are to the 2023 NEC and the 2024 Canadian Electrical Code: see references and editions.